We here at Fonzie Forever are beginning to gear up for yet another epic battle in our fantasy baseball league, and in our search came across an article about Johan Santana. The article, by Tristan Cockroft at ESPN, was entitled "Johan Santana's Decline Has Begun."
I wouldn't usually call a fantasy baseball article to everyone's attention, but Cockroft's conclusions in the article are obviously founded in reality - he believes that Santana's decline in real life will affect his fantasy value. Cockcroft, who usually does great work, concludes:
It's at this point I get on my soapbox: Johan Santana's downside is a finish outside the top 100 players of 2010 and easily out of the top 10 starting pitchers. Not only that, but I'd even argue that it's almost twice as probable an outcome as a season that puts his name into serious Cy Young discussion.I agree with much of his premise - it is of course possible that ANY player's downside is a finish outside the Top 100 fantasy players - but his main idea, that Santana is in linear decline, is incorrect.
That's not based entirely upon concerns with his ongoing rehabilitation from surgery, though that's absolutely a factor. It's more than that: Santana's declining strikeout rate, diminished velocity and the New York Mets' weakened offense are all warning signs that a collapse might be coming.
It is a common mistake by people to look at a series of values and draw a conclusion from them. It pleases people to draw conclusions, even faulty ones, from information we have at hand. If you are a given a series of numbers "2-4-6-8..." you are going to guess the next number is 10. Similarly, if you are given "2-4-8-16..." you will probably end up with 32.
For any kind of rational, mathematical system, this makes sense. However in baseball, it is faulty to look at a set of numbers trending in one direction in a linear fashion and simply to conclude that the trend will continue in that direction. Here is an example from Cockcroft:
Santana's swing-and-miss percentage -- usually a good indicator of a pitcher's strikeout potential -- has been in precipitous decline since joining the Mets, especially last season. Here are his numbers and rankings among qualified major league pitchers in the category since 2004:In a vacuum, you could easily say that his contact rate on swings will increase yet again this season. However with real life, and baseball is a great example, there are an infinite number of variables which go into numbers such as "contact rate." Could Santana have been pitching to contact? Could the NL East be loaded disproportionately with contact hitters? Could Citi Field have an excellent batter's eye?
2004: 66.3 percent contact rate on swings (1st)
2005: 74.2 percent (2nd)
2006: 74.8 percent (1st)
2007: 73.2 percent (2nd)
2008: 77.0 percent (10th)
2009: 78.4 percent (21st)
The point is, you cannot look at a simple numerical series and assume that it will continue. Doing this is how people get KILLED in the stock market. Sets of numbers -- like a contact rate, or a stock value -- are simply recordings of things that have happened in history. They carry little or no predictive value for the future.
If Santana's fastball was 90.5 MPH on average last season, what do we know about the future? Nothing. All we know is that it was 90.5 last year. Even if his fastball declined 1 MPH per season for three seasons in a row, the most reliable information that we have tells us that his fastball was 90.5 MPH last year. And since we are dealing with a human being - a flesh and bone creature which isn't beholden to any mathematical trend - my money is on his fastball being 90.5 MPH again.
Indeed, real life evidence indicates that Santana has a chance to be better this year than last. Santana himself has claimed that he feels fantastic this year, and that at times last season he couldn't even bend his elbow. He is healthier now than before - and smart money would be on him succeeding greatly this year.
As far as fantasy goes, I actually agree with Cockcroft that there are enough reasons in fantasy to not draft Santana within the first 50 picks. But rumors of Santana's decline have been greatly exaggerated.
 As for his claim that he's the best pitcher in the NL East... well... I like Santana and all, but I hear there is a new guy in Philly that might have something to say about that, not to mention a guy in Miami. It'll be very interesting to see how that shakes out.